Valve bag and method of making same



Dec. 17, 1929. HARTMAN 1,739,758

VALVE BAG AND METHODQF MAKING SAME Filed Maroh 29 1926 Lpuis l1. Hartman.

Patented Dec. 17, 1929 UNITED STATES PATENT OFFICE LOUIS H. HARTMAN, OF TOLEDO, OHIO. ASSIGNOR, BY MESNE ASSIGNMENTS, TO ST. R-EGIS PAPER COMPANY, OF NEW YORK, N. Y., A CORPORATION OF NEW YORK VALVE BAG AND METHOD OF MAKING SAME Application filed March 29, 1926. Serial No. 98,074.

My invention relates to a valve bag and method of making the same. The object of my invention is to provide a bag having a satisfactory valve witha minimum waste of material.

The details of my bag and method of making the same will appear as the description proceeds. In the accompanying drawings, forming a part of this specification, Figure 1 is a side elevation of an-end of a paper tube which is to be formed into a valve; Fig. 2 is a view similar to Fig. 1 showing a valve folded in at a corner of the tube; Fig. 3 is a view similar to Fig. 2 showing a portion of the end of the tube cut off at the valved corner; Fig. 4 is a view showing a closing seam applied to a bag end such as shown in Fig. 3; Fig. 5 is a view of a bag end such as shown in Fig. 3, with the valve unfolded; and Figs. 6 and 7 show alternative methods of disposing of some of the bag material. 7

In the accompanying drawings, showing one form of my invention, there is shown an end of a tube 10 having infolded sides or bellows-folds 11. One corner of the tube is folded in at the end ofa bellows-fold to form a valve 12. In folding in the valve the paper originally forming the apex of the bellows fold is first bent outward along line 13 from point 14 to point 15 and then bent backward upon itself from point 15 to point 16, so that the pa er originally forming the vertical apex o bellows-fold 11 is folded down to lie horizontally, anclthe severed edges of the tube originally forming a part of the end are bent inward so that they lie vertically and form the inturned edges ofthe valve.

After the valve? has been folded in this Cut. I' i 1 I .When the material in the notch is to be manner, a portionofthe end of the bag may be cut off along line 17. Then a seam is sewed along line 18, which preferably follows line parallel with the end of the tube, an at right angles to the axis of the tube,-'= until it reaches the point where the end of the tube has been cut off, and then continues in a line parallel with line 17.

I prefer to bind the end of the bag with a tape 19, bent over the end of the bag and having its edges extending below seam 18 on both sides of the bag. I prefer to extend this binding tape beyond the walls of the bag at both ends, and particularly at 20, where it extends beyond the valve. tape may be secured to the bag by adhesive as well asfby sewing if desired, and the use of adhesive at the valved corner of the bag is sometimes desirable when it is not necessary at other places, because there is a special strain upon the valved corner while the bag is being filled.

, Cutting oil the corner of the bag along line 17 after the valve is folded in is equivalent to cutting a notch in the end of the tube, as shown at 21 in Fig. 5. It will be seen that a valve extension 22 is left at thecorner of the bag, whether notch 21 is cut out before the valve is folded in or the bag is out along line 17 after the valve is folded in. I prefer to out along line 17 after the valve is folded, as that is the simplest method of cutting.

It will be readily understood that, when seam 18 is sewed, it follows dotted line 23 shown on Fig. 5 across the end of the bag, and that the folded in valve Will be caught in the seam along dotted line 24 shown in Fig. 5. In this way the seam is strengthened at the valved corner of the bag and the valve flap. is extended at 22 so as to form a more secure closure. The seam is nearer point 16 than it would be if it were sewed parallel with the end of the bag left as shown in Fig. 2. This is accomplished by the one simple straight out along line 17 The above described method of forming the valve is the preferred form; but when unusual strength is required at the valved corner it is sometimes desirable to retain the material in notch 21, instead of completing retained, I prefer'to make the desired cuts before the valve is folded in. The notch may be out along line 25, leaving the material in The binding extend outward beyond the end of the bag,

as shown in full lines in Fig. 6, and these extended flaps 27 may be bent outward to lie against the outside of the bag walls or they may be bent inward to lie between the edges of flap extension 22, as shown in dotted lines in Fig. 6. Where the bag is made of a single ply of paper, these flaps may be bent outward and pasted to the outside of the bag walls, and will considerably strengthen the valved corner of the bag. When the bag is made of a plurality of layers of paper, it is less convenient to paste the flaps in position on the outside of the bag.

When the flaps are bent inward, they are caught in the seam and form reinforcements for the inside of the seam at the top of the valve, and they also lie between the edges of valve extension 22. When a filling tube is thrust through a valve havingthe flaps on the inside, in the manner described above, the

flaps are pushed into the bag beyond the edges of extension 22, and when the filling tube is withdrawn and material inside of the bag presses towards the valve opening, these flaps are pressed against the edges of valve extension 22 and aid in forming a secure closure.

If desired, the notch may be out along line 26, before the valve is folded, leaving the material in the notch adhering to the bag walls along line 25, as shown in Fig. 7. In that case this material 28 may be bent either inward or outward, as described above. When the material is left attached to the bag walls along line 25 and folded inward or outward,

it is caught in theseam to fully as great an extent as when left connected along line 26, and there are no long ends, which are sometimes undesirable. Because there are no long ends, the flaps attached to the bag wall along line 25 have no material effect upon the closing of the valve. a

If a seam is used without reinforcing ele- 'ments, or with separate reinforcing elements upon the opposite sides of the bag, it is unnecessary to cut off the corner along line 17 but where binding tape is used passing over the end of the bag the corner must be cut off along line' 17 or folded as described above, or else a greater width is required at the binding tape valved corner'than is necessary at other points along the end of the bag.

WVhile I have described with some detail one form of my bag and a process of making the same, and have indicated some alternative features, it will be'understood that I have not attempted to' enumerate all of the variations which may be made within the scopeof the appended my invention.

Wlfat I claim is:

1. A valve bag, comprisinga tubular body. portion having one corner folded in to form a valve and having the side walls collapsed against the inturned portion and ending in a line prependicular to the axis of said body portion fromthe corner opposite the valve to claims which define a median point and on a line slanting towards the other end of the bag from said oint to the valved corner, a binding strip fol ed over the ends of said side walls, and a closing seam sewed through said binding strip and the intervening side walls.

2. A valve bag, comprising a tubular body portion having one corner folded in to form a valve and having the side walls collapsed against the inturned portion, said side walls being out off so as to end in a line perpendicular to the axis of said body portion from the corner opposite the valve to a median point and on a line slanting towards the other end of the bag from said point to the valved corner, a binding strip folded over the ends ofsaid sidewalls, and a closin seam sewed ing side walls. V 3. A valve bag, comprising a tubular body portion havin longitudinal gussets or bellows-foldsin 1ts opposite sides, having one corner folded in to form a valve, and havin the side walls collapsed against the inturned portion and ending in a line perpendicular to the axis of said body portion from the corner opposite the valve to a median point and on a line slanting towards the other end of the bag from said point to the valved corner, and a closing seam sewed through said side walls parallel with their ends.

' 4. A valve bag, comprising a tubular body portion having longitudinal gussets or bellows-folds in its opposite sides, having one corner folded into form a valve, and having the side walls collapsed against the inturned portion and ending in a line perpendicular to the axis of said body portion from the corner opposite the valve to a median point and on a line slanting towards the other end of the I bag from said point to the valved corner, a

portion having longitudinal gussets or bellows-folds in its opposite sides, having one corner folded in to form a valve, and havin the side walls collapsed against the inturne portion, said side walls being out off so as to .end in a line perpendicular to the axis of said body portion from the corner opposite the valve to a median point and on a line slanting towards the other end of the bag from said point to the valved corner, a binding strip folded over the ends of said side walls, and a closing seam sewed through said blnding strip and the intervening side walls.

6. The method of forming a valve in a bag and closing the valved end of the bag, which consists in folding in one corner of the bag to form a valve, thereafter cutting off the end of the bag beyond the valve,'whereby the foldedin portion that forms the valve would, if unfolded, extend be 0nd the adjacent portion of the end of the ag, and finally forming a closure across the end, leaving an opening through the infolded valve into the bag.

In testimony whereof I have hereunto signed my name to this specification.

LOUIS H. HARTMAN. 

